Improvement in screw-cutting dies



N.NBLS0N SCREW CUTTING DIE.

No 108,815. Papented Nnvg L 1870.

l -mmm ii sind Ctiitc.

NELS NELSON, OF GALESBURG, ILLINOIS.

, tedere Peten Ne. 108,815, aerea Nevfember 1, 1870.

*MGE- IMPROVEMENT IN SCREW-CUTTNG DIES.

The Schedule referred to in these Letters-Patent and making parl: of the same.

1, NnLS NELSON, of Galesburg, in the county ot' Knox and State of Illinois, have invented certain Improvements in Screw-plates, of which the following is a specification.

' Nature and Objects of the Invention.

bolt as required. The -other die is similarly pivoted.

to a movable plate which slides back and forth iu'a slot cut iu thc stock. In operation, any two of the corresponding faces are brought into the desired proximity so as to hold the screw-blank between them by a screw in one ot' the stock-handles which presses the die pivoted to the movable plate against the screwblauk, and the latter against the corresponding die pivotcd to the stock. By turning the handles of lthe stock,the screw is cut by the pressure of the dies against the blank, in the 'usual way.

Experience has shown that however convenient the usc ot` screw-plates so constructed, yet, from their want of rigidity during the process of cutting, they are defective, and turn out nuevenlycut` screws. The cause of this defect is obviously the unequal pressure ot' thc dies on the blank, and thc tendency of the one pivoted to the stock to turn 011 its pivot, following thc direction of the screw until brought up by the resistalice of the other die. This of course causes that edge which presses most against the blank to cut deeper than the opposite edge, and au uneven screw is the result; and while the die attached to the plate is rigidly held against the blank, and the one attached to thc stock is not, but turns slightly on its pivot, there must be an unequal pressure on the blank, especially when the point of resistance is the pivot on which v the latter die turns.

To remedy this dcfectvis the object of my improve- 1nent,aud thc invention consists in providing a key to hc inserted between the shoulder of the stock and the die pivoted thereto, so as to equalize the pressure on thc blank and securely hold the dies during the op'cration of cutting thc sercw-tln'ead thereon.

Description of l/u'Accompanying Drau-ing.

Figure l is a top plan or view of my invention. Figure 2 is abottoin view or plan.

Figurel 3 is a sectional View of fig. l on the line xx. Figure 4 is a side elevation.

General Description.

A represents the stock, attened at its central part, leaving shoulders, a a, as shown at figs. 3 and 4.

B B represent the handles,lone of which is attached to the stock A, and the other, B, is threaded and passes through a threaded hole 'in one end of the stock A, as plainly shown. n

C G' representrthe dies, which are made with a number of sides, each side ou each die being out with a diterent thread, and a side on each die being threaded to correspond with one on its fellow die.

' The die C is pivoted to and rests on the solid part of the stock A. The die G is pivoted by a bolt, c, to a plate, D, which slides in a. slot in the stock A, as shown at tig. 2. The sides of the dies, G C', which are correspondingly threaded, maybe similarly marked, as shown by the numbers 20 20, 40 40, Ste., at iig. l.

E is a key.

H is a plate.

I is a hole through the handle B.

The operation of my invention is as follows:

The die C is turned on the pivot c until the desired side is toward the die 0'; the key E is then. slipped between the die and the shoulder a, which will prevent the d-ie from turning when in operation. The die C is now turned until the correspondingly-numbered side is brought adjacent to th ie C; the plate H is then slipped up to the side of the die G,and the bolt tobe cut or threaded inserted between the dies in the usual manner. Now, by slipping the end of a punch or other small rod into the hole I, the handle B may be turned, and its threaded end, acting against the plate H and sliding the plate D and die C', will bind thc bolt being cut between the dies C C', as desired.y

The dies C C may have anynumber of faces or cutting-sides which will bring two sides always opposite to cach other.

Ola-im. I clain1 For the purposes of preventing the dies from turning and for supporting the pivots on which they turn,

thc plate H and key E, interposed respeetivel y between the dic-plate Gand the end of the screw B, and between the die-plate C andthe shoulder a, substantially as set forth.

Witnessesz NELS NELSON.

J. J. TUNNicmrr, H. H. Buma-1N. 

